Personnel location and monitoring system

ABSTRACT

A personnel location and monitoring system enables on-scene commanders in austere environments to identify, location and manage personnel. The present invention establishes a localized network of geolocation-capable transceivers which can thereafter provide communication capabilities with specially-equipped users as they ingress and egress an austere environment. Each user is equipped with an Individual Geospatial Locational Unit which provides data via a datalink with one or more of the anchors, and ultimately with a base station. From such data and the datalink itself the location of the user as well as the user&#39;s biomedical condition can be ascertained. As confidence of the location of the user drops below a predetermined threshold and/or the biomedical condition of the user raises concern with respect to the user&#39;s well-being, the present invention modifies the communication and geolocation protocols to prioritize communication and data transfer with such a user.

RELATED APPLICATION

The present application relates to and claims the benefit of priority toU.S. Provisional Patent Application No. 62/715,391 filed Aug. 7, 2018,which is hereby incorporated by reference in its entirety for allpurposes as if fully set forth herein.

BACKGROUND OF THE INVENTION Field of the Invention

Embodiments of the present invention relate, in general, to systems andmethods for locating, tracking and monitoring personnel and/or assetsand more particularly to a mobile and deployable system for dynamicallylocating, tracking and monitoring personnel indoors using a combinationof Global Navigation Satellite System (GNSS) receivers, Ultra-Wide Band(UWB) transceivers and accelerometers.

Relevant Background

Emergency scenes, involving firefighters, police, emergency medicalservices (EMS) and similar emergency-scene related, immediate services(collectively, “first-responders”; “first-responder” is abbreviated as“FR”), are characterized by chaos and confusion, yet they requiresplit-second judgment. As increasingly larger and more complex emergencysituations—such as factory, warehouse or other large-scaleconflagrations—arise, the challenge of locating and managing personnelescalates exponentially. Adding additional FR organizations and entitiesfurther complicates the problem with command-and-control (C2) issues,varying operational procedures, equipment interoperability and a host ofadditional problems arising out of differences in the various FRentities and equipment types and purposes. These added resources cancomplicate an emergency rather than remedying it. Yet the need anddesire remain to provide an on-scene commander (OSC) the ability toquickly and accurately identify, locate and monitor each FR.

Systems that locate, track and monitor the status of personnel and/orassets generally use conventional position-locating technology—forexample, GNSS technology and/or inertial/non-inertial sensors—coupledwith various signal-analysis methods. A variety of factors, however, canimpact the accuracy of those systems. For example, though the GlobalPositioning System (GPS)—a type of GNSS (for purposes of this document,“GNSS” and “GPS” may be used interchangeably)—has proved to be a veryuseful location and navigation tool for outdoor applications, a numberof barriers impair or bar the use of GPS for indoor applications.Geolocation through GPS is achieved via method known as“multilateration” (also known as “ranging”, abbreviated as, “MLAT”).MLAT is a ranging method that measures the time of flight from GPStransmitters in space to a GPS receiver on Earth. The distances coveredby the signals from the GPS satellites—all transmitting the same type ofsignal at the same time—are the radii of circles whose circumferencesupon which the receiving object's position must lie. Since the object'sposition can lie only along the circles' circumferences, theintersection of these arcs must be the object's position. While theestablishment and refinement of GPS has tremendously advanced theability to locate an object, this system is not without its limitations.These limitations stem from the fact that GPS receivers must maintain adirect, line-of-sight with at least four transmitting GPS satellites foraccurate positioning. GPS can thus become unreliable in urbanenvironments, mountainous terrain, inside buildings, underground, oranywhere else where line-of-sight with at least four GPS satellitescannot be maintained. Moreover, electromagnetic interference along GPSsignal paths can degrade or deny positional data, as can GPS signalattenuation and/or so-called “multipath” impacts (GPS signal reflectionsoff structures—especially prevalent in “urban canyons” [environmentsdensely-populated with tall-buildings, e.g., cities]). Thus, in indoorenvironments and within close proximity of urban building structures,line-of-sight paths to GPS satellites may be substantially blocked andGPS signals may be highly degraded, rendering GPS signals attenuatedtypically several orders of magnitude and thus making accurate positiondeterminations difficult or impossible.

Beyond GNSS-based position-location methods, however, an object'slocation can also be determined through MLAT methods usingnon-space-based transmitters, such as local transmitters. A cell toweris good example of such a local transmitter. Using three or more localtransmitters whose position is known, the location of an object—such asa cell phone—can be determined. Knowing the positions of the celltowers, the phone's relative location can be overlaid on a map,transforming its local (or relative) position to a geospatial referenceframe. But this method, too, has shortfalls. Transmitter availability isoften limited, and cell-tower transmissions also suffer fromline-of-sight limitations. Moreover, the location of each tower isfixed, and the capital infrastructure needed for such towers issubstantial.

A need exists for a mobile, local (or relational) system that cansynthesize various positioning systems' information and schema toprovide adaptive, robust and reliable positional information on FRs tothose in positions of FR C2 regardless of environmental conditions orlimitations imposed by the physical structures within which FRs mustoften offer emergency response. These and other deficiencies of theprior art are addressed by one or more embodiments of the presentinvention.

Additional advantages and novel features of this invention shall be setforth in part in the description that follows, and in part will becomeapparent to those skilled in the art upon examination of the followingspecification or may be learned by the practice of the invention. Theadvantages of the invention may be realized and attained by means of theinstrumentalities, combinations, compositions, and methods particularlypointed out in the appended claims.

SUMMARY OF THE INVENTION

Disclosed is a system for geolocation in austere environments where aLocation Processing Engine (LPE) is configured to respond to firstresponder User Biometric Data (UBD) and locational information—either ofwhich has degraded below a predetermined limit—by modifying dwell timeassignments (defined below as “comm windows”) to increase confidence inthe FR's Individual GeoLocation Unit (IGLU) location (IL). Such a systemcan include, in one embodiment, one or more anchors having at least oneUWB transceiver as well as a GNSS receiver configured to determine anAnchor Location (AL). It can also include at least one IGLU, associatedwith a user (i.e., an FR), that has a UWB transceiver that can providetwo-way ranging to anchors positioned around the austere environment.Each IGLU includes accelerometers configured to measure the motion ofthe user, and a Biometric Monitoring Unit (BMU) configured to measureUBD. Finally, the system includes a base station communicatively coupledto each anchor and/or each IGLU in a localized network bounded by theanchors. The LPE resides in the base station and the base station alsoincludes a UWB transceiver which receives IGLU data from each IGLU,either directly from each IGLU or relayed through one or more anchors.The LPE determines an IL based on received IGLU data and assignsperiodic dwell time as a function of the UBD and LPE confidence in theIL.

Each IGLU is configured to transmit, using at least one UWB transmitter,IGLU data using one or more data packets. Each IGLU also relays the ILof other IGLUs to the base station and/or to one or more anchors. Thebase station determines IL using MLAT of received IGLU data and GNSSdata of each anchor. The LPE is then configured to respond to IL fallingbelow predetermined limits, based on UBD or IL confidence, to modifydwell time assignments.

The method used for geolocation of a user in austere environmentscomprises establishing a local geolocation network by one or moreAnchors wherein each anchor is associated with an AL, and each anchorincludes at least one UWB transceiver and a GNSS receiver. One of theanchors is configured as a base station having an LPE, which isassociated with the users IGLU. Each IGLU includes at least one UWBtransceiver configured to provide two-way ranging, a plurality ofaccelerometers configured to measure the motion of the user, and aBiometric Monitoring Unit (BMU) configured to measure User BiometricData (UBD) of the user. Using MLAT of received IGLU UWB data and the UWBand GNSS data of each anchor, as well as the IGLU data itself, the basestation determines the IGLU's location (IL) and establishes a periodicdwell time based on indicated distress levels and LPE confidence in theIL.

In another version of the present invention, a non-transitory,machine-readable storage medium stores instruction for personnelgeolocation in an austere environment. Such a medium includesmachine-executable code that, when executed by at least one machine,causes the machine to associate with each user, an IGLU which has atleast one UWB transceiver configured to provide two-way ranging. EachIGLU also includes a plurality of accelerometers configured to measurethe motion of the user, and a Biometric Monitoring Unit (BMU) configuredto measure UBD of the user. Additional code directs the base station toreceive IGLU data and thereafter determine an IGLU location (IL) basedon the received IGLU data. The LPE of the base station executes code todetermine a LPE confidence in the IL, and assign a periodic dwell timeas a function of the UBD and LPE confidence in the IL. Additional codecauses the IGLU to transmit IGLU data contained within one or more datapackets. Anchors are directed to relay this information to the basestation which thereafter uses MLAT of the UWB and GNSS data of eachanchor to determine a location of the IGLU.

The features and advantages described in this disclosure and in thefollowing detailed description are not all-inclusive. Many additionalfeatures and advantages will be apparent to one of ordinary skill in therelevant art in view of the drawings, specification, and claims hereof.Moreover, it should be noted that the language used in the specificationhas been principally selected for readability and instructional purposesand may not have been selected to delineate or circumscribe theinventive subject matter; reference to the claims is necessary todetermine such inventive subject matter.

BRIEF DESCRIPTION OF THE DRAWINGS

The features of the present invention and the manner of attaining themwill become more apparent and the invention itself will be bestunderstood by reference to the following description of one or moreembodiments, taken in conjunction with the accompanying drawings:

FIG. 1 shows a high-level system architecture for a personnel locationand monitoring system, according to one embodiment of the presentinvention;

FIG. 2 represents a high-level depiction of a deployed scenario in whicha system for personnel location and monitoring, according to the presentinvention, is implemented;

FIG. 3 represents a high-level depiction of a deployed scenario in whichthe resilient, adaptive communication feature of the present invention,is implemented;

FIGS. 4A-4L present a flowchart of communication protocols betweenvarious components of a system for personnel location and monitoring,according to one embodiment of the present invention; and

FIG. 5 is a flowchart of one embodiment of a methodology for personnellocation and monitoring according to the present invention.

The Figures depict embodiments of the present invention for purposes ofillustration only. One skilled in the art will readily recognize fromthe following discussion that alternative embodiments of the structuresand methods illustrated herein may be employed without departing fromthe principles of the invention described herein.

DESCRIPTION OF THE INVENTION

A system, and its associated methodology, provides personnel locationand monitoring capability to OSCs in austere environments. The presentinvention establishes a localized network of geolocation capabletransceivers around an austere environment which can thereafter providecommunication (datalink) capabilities with specially-equipped users(FRs) as they ingress and egress an austere environment. The localizednetwork of the present invention is formed from a plurality oftransceivers hereinafter referred to as anchors, one of which isdesignated as a base station. Each anchor, including the base station,includes, among other things as described below, a GPS receiver and oneor more UWB transceivers.

Each user (an FR, in one embodiment) is equipped with an IGLU whichprovides data via a datalink capability with one or more of the anchors,and ultimately with the base station. From such data and the datalinkitself the location of the user and that user's biomedical condition canbe ascertained. The IGLU communicates with the base station, eitherdirectly or through an anchor, enabling the base station to monitor thephysical condition of the user and the user's location. As confidence ofthe location of the user drops below a predetermined threshold and/orthe biomedical condition of the user raises concern for the user'swellbeing, the present invention modifies the communication andgeolocation protocols to prioritize communication and data transfer withthe user's IGLU.

Embodiments of the present invention are described below in detail,referencing the accompanying Figures. Although the invention has beendescribed and illustrated with a certain degree of particularity, it isunderstood that the present disclosure has been made only by way ofexample and that numerous changes in the combination and arrangement ofparts can be resorted to by those skilled in the art without departingfrom the spirit and scope of the invention.

The following description with reference to the accompanying drawings isprovided to assist in a comprehensive understanding of exemplaryembodiments of the present invention as defined by the claims and theirequivalents. It includes various specific details to assist in thatunderstanding but these are to be regarded as merely exemplary.Accordingly, those of ordinary skill in the art will recognize thatvarious changes and modifications of the embodiments described hereincan be made without departing from the scope and spirit of theinvention. Also, descriptions of well-known functions and constructionsare omitted for clarity and conciseness.

The terms and words used in the following description and claims are notlimited to the bibliographical meanings, but, are merely used by theinventor to enable a clear and consistent understanding of theinvention. Accordingly, it should be apparent to those skilled in theart that the following description of exemplary embodiments of thepresent invention are provided for illustration purpose only and not forthe purpose of limiting the invention as defined by the appended claimsand their equivalents.

By the term “substantially” it is meant that the recited characteristic,parameter, or value need not be achieved exactly, but that deviations orvariations, including for example, tolerances, measurement error,measurement accuracy limitations and other factors known to those ofskill in the art, may occur in amounts that do not preclude the effectthe characteristic was intended to provide.

Like numbers refer to like elements throughout. In the figures, thesizes of certain lines, layers, components, elements or features may beexaggerated for clarity.

The terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting of the invention. Asused herein, the singular forms “a,” “an” and “the” are intended toinclude the plural forms as well, unless the context clearly indicatesotherwise. Thus, for example, reference to “a component surface”includes reference to one or more of such surfaces.

As used herein any reference to “one embodiment” or “an embodiment”means that a particular element, feature, structure, or characteristicdescribed in connection with the embodiment is included in at least oneembodiment. The appearances of the phrase “in one embodiment” in variousplaces in the specification are not necessarily all referring to thesame embodiment.

As used herein, the terms “comprises,” “comprising,” “includes,”“including,” “has,” “having” or any other variation thereof, areintended to cover a non-exclusive inclusion. For example, a process,method, article, or apparatus that comprises a list of elements is notnecessarily limited to only those elements but may include otherelements not expressly listed or inherent to such process, method,article, or apparatus. Further, unless expressly stated to the contrary,“or” refers to an inclusive or and not to an exclusive or. For example,a condition A or B is satisfied by any one of the following: A is true(or present) and B is false (or not present), A is false (or notpresent) and B is true (or present), and both A and B are true (orpresent).

As used in this discussion, “UWB” is a radio frequency (RF) technologyusing extremely short-duration RF energy pulses. The extremelyshort-duration pulses in the time domain translate to a very widefrequency-domain spectrum (typically more than 1 GHz wide). Thetechnology can be used for communications, radar and ranging/locationapplications. UWB systems transmit signals across a much wider frequencythan conventional systems and are well suited to use in environmentssuch as automobiles and buildings, because of their very compact size,fine spatial resolution, extraction of target feature characteristics,low probability of interception and non-interfering signal waveform—allof which make UWB systems appealing to such applications.

Unless otherwise defined, all terms (including technical and scientificterms) used herein have the same meaning as commonly understood by oneof ordinary skill in the art to which this invention belongs. It will befurther understood that terms, such as those defined in commonly useddictionaries, should be interpreted as having a meaning that isconsistent with their meaning in the context of the specification andrelevant art and should not be interpreted in an idealized or overlyformal sense unless expressly so defined herein. Well-known functions orconstructions may not be described in detail for brevity and/or clarity.

It will be also understood that when an element is referred to as being“on,” “attached” to, “connected” to, “coupled” with, “contacting”,“mounted” etc., another element, it can be directly on, attached to,connected to, coupled with or contacting the other element orintervening elements may also be present. In contrast, when an elementis referred to as being, for example, “directly on,” “directly attached”to, “directly connected” to, “directly coupled” with or “directlycontacting” another element, there are no intervening elements present.It will also be appreciated by those of skill in the art that referencesto a structure or feature that is disposed “adjacent” another featuremay have portions that overlap or underlie the adjacent feature.

Spatially relative terms, such as “under,” “below,” “lower,” “over,”“upper” and the like, may be used herein for ease of description todescribe one element or feature's relationship to another element(s) orfeature(s) as illustrated in the figures. It will be understood that thespatially relative terms are intended to encompass differentorientations of a device in use or operation in addition to theorientation depicted in the figures. For example, if a device in thefigures is inverted, elements described as “under” or “beneath” otherelements or features would then be oriented “over” the other elements orfeatures. Thus, the exemplary term “under” can encompass both anorientation of “over” and “under”. The device may be otherwise oriented(rotated 90 degrees or at other orientations) and the spatially relativedescriptors used herein interpreted accordingly. Similarly, the terms“upwardly,” “downwardly,” “vertical,” “horizontal” and the like are usedherein for the purpose of explanation only unless specifically indicatedotherwise.

FIG. 1 presents a high-level system depiction of a personnel locationaland monitoring system 100. According to one embodiment of the presentinvention, a FR locational and monitoring system 100 increasessituational awareness at all levels of a FR incident scene, from theindividual FR to command and control levels. For purposes of the presentinvention, the term “incident” is understood to mean any event requiringFR response, and the event includes the period during which the FR ison-scene and the system of the present invention is active. Further, theterm “incident scene” is understood to mean any incident setting inwhich a FR is needed. The system of the present invention furtherprovides a digital record of each incident, enabling digitalreconstruction of the incident (or set of incidents) for training orindividual/group assessment.

One embodiment of the present invention is comprised of severalnetworked components. One component, referred to herein as a “basestation” 116, includes a Location Processing Engine (LPE) 115—that is, amicro-form-factor PC or other capable processor, a non-transitorystorage medium (which provides, among other things, local storage ofincident telemetry as well as storage of a prioritized rule set used toassign communication priorities within the system's network)—combinedwith an application programming interface (API) application, and arouter (that is, a commercial, stand-alone router), as well as at leastone UWB transceiver 114 and at least one GNSS 118 receiver.

Another component, an “anchor” 120, provides a static reference pointfor MLAT calculations. The anchor is a mobile, deployable, staticreference and communication/navigation (“comm/nav”) point deployed by FRpersonnel during initial on-site incident assessment. In one embodiment,each anchor has a processor (not shown) on board and provides externalcommunications via a UWB transceiver 124, along with GNSS-assistedpositioning from an on-board GNSS receiver 128 and on-board memory. Eachanchor also includes a 9-degree-of-freedom (9D)accelerometer/gyroscope/magnetometer (AGM) 126 for inertial measurements(the term, “9D”, derives from accelerometer measurements of position [inthree dimensions], gyroscopic attitude measurements [object orientationin three dimensions] and geomagnetic sensor measurements of the Earth'smagnetic field [again, in three-dimensional space]). Each anchor is, inone embodiment, supplied by a 3200-milli-amp-hour (3.2K mAh) batteryproviding approximately 8 hours of continuous active run-time, and each3.2K mAh battery uses built-in inductive charging according to the “Qi”Wireless Power Consortium standard (the standard abbreviated in thisdocument as, “Qi-WPC”). The anchor has a durable weather-resistantcasing whose firmware is capable of being updated by over-the-air (OTA)updating through UWB transmissions. MLAT positioning fidelity increasesas more anchors are deployed. In one embodiment of the present inventionthe base station is a specially equipped anchor. In other embodimentsthe base station is a more capable centrally located component thatinteraction with and manages the deployed anchors to form the localizednetwork.

Another component in this system is an Individual Geospatial LocatingUnit (IGLU) 140. An IGLU is worn by each FR during incident response.Each IGLU transmits the geolocation and biometric information of theindividual, IGLU-equipped FR. According to one embodiment of theinvention, each IGLU provides external communications via UWBtransceivers 144 (as well as to its associated Biometric Monitoring Unit(BMU) 150, via a Bluetooth link, as detailed below). Each IGLU 140further employs an AGM 146 for accelerometer-derived positiondetermination (relative 3D-positioning updates) using the internalmotion sensors of the AGM, and each IGLU sources power from a 2000-mAh(2K mAh) battery holding approximately 8 hours continuous activerun-time. Finally, each IGLU is paired to and retrieves and reportsbiometric telemetry from its associated BMU via Bluetooth.

The BMU 150, like the anchor 120, IGLU 140 and EEL 170 (the EEL will bediscussed below) has a durable, heat & weather-resistant casing and usesAtmel architecture. The BMU 150 communicates with the IGLU 140 via aBluetooth communication link and has, in one embodiment, an on-board 32KB FRAM. Like the IGLU 140, anchor 120 and EEL 170, the BMU 150 isOTA-firmware-update-capable. Further, the BMU 150 has built-in inductivecharging (Qi-WPC) and contains a high-resolution infrared oximeter andpulse sensor, as well as a 500-mAh battery which provides a continuous,active run-time of approximately 8 hours. The BMU 150 is worn with theIGLU 140 by FR personnel during incident response and the primaryfunction of the BMU is to report biometric (biomedical) telemetry viaBluetooth to the associated IGLU for UWB relay, ultimately, to the basestation.

In another embodiment and as alluded to above, an optional component ofthe present invention is a comm/nav relay known as an EEL 170 (“EEL” isthe acronym for “Emergency Egress Locator”). EELs provide additionalstatic points of reference as well as additional comm/nav coverage(signal relay, or effectively, signal amplification), and are typicallydeployed by FRs during structure ingress. EELs are lightweight versionsof anchors that can be deployed within a distressed structure (e.g., abuilding on fire) to provide additional static reference points for UWBranging and communication. EELs do not, in this embodiment, contain AGMsor GPS receivers, but do contain at least one UWB transceiver 174. EELsalso contain a consumable adhesive mount, enabling a FR to “slap” itonto any adhering surface, for ease in rapidly positioning the EELduring ingress (or as needed, when otherwise-denied-coverage areasbecome apparent). A FR would typically place an EEL in an area wherediminished comm/nav capability would otherwise be expected to exist(e.g., due to debris, obstructions, deep FR penetrations intostructures, etc.).

Although the invention has been described and illustrated with a certaindegree of particularity, it is understood that the present disclosurehas been made only by way of example and that numerous changes in thecombination and arrangement of parts can be resorted to by those skilledin the art without departing from the spirit and scope of the invention.

In one embodiment of the present invention and with additional referenceto FIG. 2, the invention is deployed as a system upon arrival at anincident scene. For example, firefighters responding to a building firewould identify the building 210 and its immediate environs as anemergency response incident and establish a C2 perimeter around theincident area. While this particular example is an incident involving abuilding fire and an incident response by a fire-fighting team, one ofreasonable skill in the relevant art will appreciate that the system andmethodology presented in this example are applicable to a wide varietyof situations and environments in which locating and monitoring FRpersonnel is important.

Location of each member of the responding team is maintained andmonitored by the base station which, along with associated (i.e.,registered) anchors, IGLUs and EELs (as needed), establish a local UWBnetwork. FRs initially deploy a plurality of anchors 120 along aperimeter of the incident scene, with each anchor providing a differentvantage of the structure. Ideally, the perimeter anchors surround theincident scene. Each anchor is positioned to be within line-of-sight ofone or more other anchors and each anchor includes, in one embodiment, aplurality of UWB transceivers (in addition to the items detailed above).Each anchor provides a static, known location that can communicate viaUWB comm/nav links to the base station as well as to one or more IGLUs140 worn by the FRs.

Once the network has been established, the base station 110 constructsthe communication window table for the network. “Communication windowtable” is understood to mean a table (“timetable”) of time periods (or“comm windows”), with each comm window defined as the transmit/receiveperiod allocated by the base station to a particular device (IGLU,anchor or EEL). Each UWB-capable device in the network is allocated acomm window during which the base station will transmit signals to andreceive signals from that device.

Each FR carries an IGLU 240, 242 specifically identified with thatindividual. Each IGLU remains in a semi-dormant state until receipt of abase station 110 communication, after which the IGLU “wakes up” andperforms device registration with the base station. Each IGLU 240, 242also initializes communication with its associated BMU, via a dedicatedBluetooth-communication-standard (“Bluetooth”) communication link, afterwhich each BMU unit then also “wakes up” and begins its self-calibrationprocess. Once the self-calibration process is completed, each BMUmonitors, among other things, the heart rate and oxygen (02) saturationlevels of the BMU's wearer. With registration complete, the base station110 assigns a communication sequence slot (the above-referenced commwindow) to each associated IGLU, EEL and anchor, as a function of thetotal number of UWB-capable units registered on the UWB network and theaverage time required to process the data packets received from eachunit. As used in this document, the processing through each of thesecomm windows by the base station to exhaustion of the total number ofcomm windows assigned to devices registered on the network is termed a“cycle”, and the base station continuously processes through thesecycles while the system is operating. During the start of each cycle,the base station sends out a reference signal to synchronize thenetwork-associated clock of each unit within the base station's localUWB network. During this cycle the base station also provides anyadditional information about new sequences or slots which have beenissued (based upon the discovery of any new units which have arrivedon-scene since the initial establishment of the communication windowtable). Each unit broadcasts any reportable data as well as any receivedreportable data or telemetry data from other units.

Each IGLU transmits its location via the UWB network to the basestation, and the base station computes the IGLUS location by applyingstandard TDOA and TOF techniques to received signals from devices withinthe UWB network. A reference location is continually updated andmaintained by each IGLU using the UWB signals and communicated back tothe base station. The OSC can use this information to identify andlocate each member of the incident response team from a central point ofcontrol.

Referencing in addition FIG. 3, As FRs ingress into a structure RFsignals may become degraded or attenuated, making UWB-based ranging andcorresponding location 320 determination unreliable. WhileUWB-technology signals are less susceptible to degradation due tostructural barriers (and hence are advantageous for use in the presentinvention), they nonetheless are still subject to environmental and/orstructural factors and can become unreliable. The present invention thusmerges inertial location data drawn from the IGLU's AGM with that ofreceived UWB transmissions to dynamically update each IGLU's referencelocation within the base station, through its LPE. As UWB transmissionsfade and become unreliable, AGM sensors are used to determine the IGLU'slocation based on inertial motion from the IGLU's last know location.Movements are tracked, and locations determined using the AGM'saccelerometers, as detailed below. Upon receipt of a reliable UWB signalfrom one or more anchors 120, the accelerometer drift is corrected andthe IGLU's location is reset. The constant signal strength and erroranalysis of UWB signals combined with accelerometer inertialcalculations dynamically corrects and resets each IGLU's location withinthe structure.

According to one embodiment of the present invention, an algorithm isapplied by the LPE during each cycle to measure the reliability ofaccelerometer data against TDOA/TOF-derived MLAT calculations fromreceived UWB transmissions sent by the static UWB reference points(i.e., the anchors and EELs whose UWB transmissions have been receivedby the base station). The algorithm on the IGLU determines whatadditional information will be reported by the IGLU, in addition to itstransmission “time stamp” (i.e., the IGLU's best estimate of the exacttime the IGLU sends the transmission), to the base station. Each IGLUrecords and stores AGM data and its last-known location, as updated bythe received base station UWB transmission. The base station weighs theIGLU's AGM data against MLAT calculations derived from available staticUWB reference points, prioritizing the base station's reference ofreliability.

In one embodiment of the present invention a linear-graded scale is usedto assess signal reliability as the IGLU moves away from a given anchorpoint. In such an instance, the farther away the IGLU is from thatanchor the less that anchor's data will be weighted in the determinationof the IGLU's location. In related fashion, accelerometers—includingthose of the AGM—are known to possess certain “drift” (that is,inaccuracies in position, usually measured as velocities—for example, ifan accelerometer has a drift of 1 kilometer per hour, in one hour theaccelerometer-calculated position of an object will be 1 kilometer inerror from the object's actual position) and can become unreliable aftera period of time. The present invention, in one embodiment, uses agradient scale based on the amount of time elapsed since the lastverification-of-location transmission by the base station. The scaleprovides an uncertainty score for the AGM which is compared to that ofthe UWB uncertainty score to calculate a hybrid, “best estimate”position for the IGLU.

In environments in which UWB reception is questionable EELs can bedeployed to provide additional UWB relay points. Each relay is a UWBtransceiver positioned at a static, known location (as calculated by thebase station), thus its positional data can be used to update an IGLU'slocation and also serve as a communication relay.

In one embodiment of the present invention, for example, MLAT methodsare applied to UWB-generated signals to determine the relative positionof a device. Positions of devices (anchors and IGLUs) containing AGMsare also updated by AGM measurements. These inertially-derivedmeasurements are then algebraically summed to the last-received positionacknowledgment from the base station to provide a current-positionupdate as follows: Each AGM-containing device houses two registers. Thefirst, “R1” 250, contains the last-received position acknowledgment fromthe base station. The second, “R2” 252, contains inertial measurementsfrom the device's AGM, and these inertial measurements are constantlyupdated. During the associated comm window, each device (anchor/IGLU)transmits its R1 250 and R2 252 values, from which the base stationcomputes a “new” R1 value and transmits the same, along with other data(as prioritized by the base station's prioritization algorithm), back tothe device (either directly or through the UWB network). The device thenoverwrites its R1 with the new R1 value and “zeroes-out” (clears) its R2values for the new acceleration coefficients that will be applied to thenewly-received R1 value, in the same manner as previously described,continuing in this fashion throughout the operation of the system.

FIG. 2 shows a high-level, overhead overview of one embodiment of theinvention, as a system operating with no anomalies in eithercommunication or in position determination. Here, the system is set upupon arrival at an incident scene, which in this case is a distressedbuilding. Anchors 120 A1, A2, A3 and A4 are positioned around thebuilding 210 within line-of-sight of each other, and IGLU is outside thebuilding, respectively. The base station 110 B5 is embodied as a firetruck equipped with the system-embodiment of the present invention.

As detailed earlier, when IGLU 240 “wakes up” (after being turned on),it first determines whether it is registered on the network. If it isnot, it broadcasts a registration data packet to the base station,either directly or through the UWB network (i.e., as relayed through anyavailable network-registered UWB device). Once IGLU has received anacknowledgment it is registered on the local UWB network, it thenretrieves its stored velocity/bearing data and prepares a “positioningpacket” for transmission through its UWB transceiver to any-and-allother available transceiver(s), including those on the base station. Itnext determines if it is paired to its BMU and if so, interrogates theBMU for biometric data, which the BMU sends to IGLU across its pairedBluetooth link. It then prepares these two data packets (BMU data andpositional [R1 & R2] data) to be sent as a single data packet duringIGLU's comm window.

After the data retrieval and preparation described immediately above,IGLU must then “sync up” to the “new” timetable transmitted by the basestation across the UWB network (the timetable's calculation is discussedabove). Upon reception of the timetable, IGLU synchronizes its localclock to that of the network (the network's reference-clock signal isestablished and broadcast by the base station), then processes andstores the timetable internally, then retransmits the timetable acrossthe UWB network and awaits the start of its comm window.

During the timetable's cycle, IGLU—like every UWB-equipped device in thenetwork (i.e., anchors, EELs and IGLUs)—transmits and receives in itscomm window and has a “standby window” during which it performs othertasks, outside the comm window. At the start of IGLU's comm window, IGLUdetermines whether any existing data packets remain from the end of thelast comm window to transmit and, if so, it queues them for transmissionahead of the current packets, so that through iterations of comm windowsall packets in IGLU's packet-queueing are eventually transmitted.

In contrast, during IGLU's standby window it gathers rawvelocity/bearing sensor data (from its AGM) and calculates and storesits movement differential (R2) since its last acknowledged (from thebase station) position (R1) transmission. It then examines any datapackets received from the base station (including, but not limited to,the base station's LPE-computed last-position of IGLU) and the otherUWB-equipped devices, storing valid packets and discarding the rest. Ifa new R1 value is received in the received data packets, it replaces theold R1 and R2 is simultaneously reset to zero movement-differential fromthe new R1 value.

No positioning calculations are performed outside the LPE, whichprocesses TDOA/TOF values from all received data packets usingconventional MLAT methods to determine device locations. Each deviceprecisely “time-stamps” its data when it sends a data packet, and sinceelectromagnetic signals travel at the speed of light, simpletime-rate-distance calculations can provide the LPE information from thevarious devices using these MLAT methods to determine each device'sposition. The base station, thus, does not only receive data packetsfrom UWB-equipped devices on its network, but the signal sending thedata packet is used itself for ranging. For instance, in FIG. 2, A1 120and A4 120 both receive time-stamped data-packet transmissions from IGLU240. Each anchor then “stamps” its own time on its data packettransmission, and forwards IGLU's data packet with its transmission. Thebase station's 110 LPE then processes all data packets to determinepositions. Here, for instance, the LPE “knows”, based on knowing A1'sand A4's absolute positions (in a manner similar to this discussion) andthe difference between the time IGLU's data was transmitted and the timeit arrived at A1, IGLU 290 must lie somewhere on C1 260, thecircumference formed by the constant-length distance IGLU must be fromA1. In similar fashion, IGLU 240 must lie on C4 265, with respect to A4.

Using such MLAT techniques, IGLU can be found at the intersection of theintersecting arcs of the circumferences of each such circle from eachdevice receiving a valid data packet from IGLU, assuming each suchdevice then successfully transmits its own data packet along with thatof IGLU to the base station, eventually. Here, “eventually” simply meansthe data packets could undergo many “relays” through other IGLUS, EELsor anchors before arriving at the base station for LPE positionprocessing and determination.

In contrast, FIG. 3 is a high-level, overhead overview whencommunication (here, “communication” means communication via a UWBtransceiver) or position-locating anomalies are introduced. In oneembodiment of this invention, using the same configuration as in FIG.2—A1-A4, the base station and IGLU—a communication and/or positioningproblem has arisen. The two problems can of course be related, as in thecase of a communication problem in which no communication is receivedfrom IGLU's UWB transceiver. In that case, a positioning problem willalso arise, since the LPE will not have received updated positioningdata from IGLU. But the problems can be distinct, as well.

In the case of a communication problem, if communication is lost betweenIGLU and the base station (either directly or as-relayed through ananchor, EEL or another IGLU) for more than a predetermined period oftime, the base station will “lock” the comm window for IGLU so that evenwhen the base station transmit a “new” timetable, IGLU's comm window isnot adjusted. Moreover, after another predetermined period expires, thebase station “rachets” that window open periodically, as a function oftime, widening both sides of the IGLU comm window for increased dwelltime for “listening” for UWB signals from IGLU, until the problem isalleviated (i.e., updated IGLU data arrives directly or through a relayto the base station).

In cases where a substantial amount of time has lapsed sincecommunication (directly or indirectly) between the base station andIGLU, LPE position “confidence” 230 in IGLU's position will alsoattenuate (since this, too, is a function of time and based onpredetermined thresholds of positioning confidence maintained by theLPE), thus a communication outage will eventually result in aposition-confidence degradation within the LPE, as well.

The converse, however, is not true: A position-confidence problem doesnot of itself imply a communication problem. It is possible, forinstance, for the LPE's composite confidence in both IGLU's AGM-derivedposition (R1, as updated by R2) and UWB-derived MLAT measurements thatthe LPE's position-confidence in IGLU's position drops below anacceptable threshold, even though it receives—via direct or relayed UWBtransmissions—data packets from IGLU. This is especially true as moreUWB links accrue through which IGLU's signal must be relayed. In thiscase, again, the comm window for IGLU will be locked based uponpredetermined criteria so that better positioning data can potentiallybe gained by the base station and processed through the LPE, and IGLU'scomm window will be ratcheted open as discussed above.

As discussed previously, UWB signals are inherently robust forcommunication within structures. UWB technology enables very high datarates, low power consumption and inherent resistance to structural andmultipath impacts make such technology desirable for indoor-locationapplications. Even so, even UWB signals can become attenuated, degradedor distorted from environmental and/or structural impacts. Still FRsmust be able to be located in such less-than-optimum conditions, whichone embodiment of the present invention overcomes through its adaptive,resilient communication and positioning.

Returning to the above discussion about the functioning ofUWB-equipped-device registers R1 and R2, FIG. 3 shows IGLU 242 in abuilding 210, but communication between the base station 110 and IGLU242 has been lost. In this case, R1 will remain the “old” valuelast-received by IGLU from the base station, and R2 will continuouslystore positional “offsets” (three-dimensional displacement values fromR1) as updated by continuously-fed AGM values. Unlike conventional MLATrequirements, in one embodiment of this invention only one UWBcommunication link (direct or indirect) is needed between IGLU and thebase station. In that case, as long as IGLU can send and receive via theone UWB path (i.e. to and from a single UWB transceiver in the network,whether on the base station or otherwise), IGLU will transmit its R1 andR2 values as detailed above and the base station will return an updatedR1 value to IGLU, which will update its R1 and “zero out” R2, asdescribed above. Now, if sufficient time elapses, a predeterminedtolerance threshold will again be reached in which the LPE'sposition-confidence in IGLU's position will deteriorate, triggering thecomm-window-lockdown and ratchetting discussed above. Nonetheless,position-updating is available before such thresholds are reached, eventhough only a single UWB comm pathway exists between the base stationand IGLU, and no other ranging-useful data is available from any otherUWB-equipped network device.

FIGS. 4A-4L present a cycle-based flowchart, in one embodiment of thepresent invention's methodology. Bordering the left side of theflowchart and starting at the top are the phases of the cycle, labeled,“Cycle Prep” 405, “Cycle Sync” 407, “Cycle Execution” 409 and“Off-Cycle” 410. Upon power-up, each UWB-equipped system component willbe in the “Off-Cycle” 410 mode (“Off Cycle”) until registered on the UWBnetwork with the base station. Each device will immediately determinewhether it is registered 411 (“Is Device Registered?”) and if not(“No”), the unregistered device will send 412 a registration packet tothe base station (“Send Registration Packet to Base”), requestingnetwork registration, and await 413 the base station's reply (“AwaitCycle Prep Response”), which will occur during the “Cycle Prep” 405(“Cycle Prep”) phase, as next discussed.

Beginning with the base station, at the start 402 of the Cycle Prepphase (“Cycle Start” in “Cycle Prep” phase), the base station evaluates404 the last received transmissions (“Evaluate Last ReceivedTransmissions”) using a predetermined, prioritized list of evaluationcriteria (e.g., BMU data indicating degraded FR health, missed IGLUcomm/nav windows, etc.). Additionally, a determination of whether anydevices require additional time 406 (i.e., wider comm windows) is made(“Do Any Devices Require Additional Comms Time?”) and if so (“Yes”),calculations are made to determine the additional comm window lengthrequired (“Calculate New Communication Window Needed For AdditionalComms”) 408. Otherwise (“No”), the next question is whether any devicesare not in communication (directly or through another UWB-capabledevice) with the base station (“Have Any Devices Lost Comms?”) 415. Ifso (“Yes”), then the base station—through its LPE—locks the device'scomm window (“Lock Comms Window For Missing Device”) 416 to ensure thedevice's comm window is “sanitized” to listen solely for the missingdevice and that the comm window is not reallocated to any otherdevice(s). If no device has lost communication with the base station(“No”), then the next question is whether any new device has registeredon the base station's local UWB network (“Have Any New DevicesRegistered On The Network?”) 417. If so (“Yes”), the base stationidentifies the new device(s) allocates time 414 for new devices andtransmits an acknowledgment of the same to the new device(s) (“TransmitIncident Comms ID To Registering Device”) 418. If no new devices haveregistered (“No”), the base station then determines whether, based onany “Yes”-answers to the previous questions, a new timetable is needed(“Is a New Timetable Needed?”) 419. If so (“Yes”), then the base stationcomputes and generates 420 an updated (“new”) timetable and broadcaststhe same across the UWB network (“Transmit New Timetable”) 421, thenawaits the start of the Cycle phase (“Await Cycle Start” 422, at the endof the “Cycle Sync” phase).

At the beginning of the “Cycle Sync” 407 phase (“Cycle Sync”), the basestation transmits a new timetable (“Transmit New Timetable”) 421, thenawaits the start of the Cycle Execution phase (“Await Cycle Start”) 422.

At the beginning of the “Cycle Execution” phase (“Cycle Execution”) 409,the base station gathers positional information from data packetstransmitted directly from devices within the UWB network, or through thenetwork itself (“Gather Raw Velocity/Bearing Sensor Data”) 423. For eachsuch data packet (“Packet Received”) 424, the base station firstdetermines whether the packet is valid (“Is Packet Valid?”) 425. If thepacket is not (“No”), it is discarded (“Discard Packet”) 426. If it isvalid (“Yes”), then a determination must be made as to whether thepacket is new (“Is Packet New?”) 427. If the packet is not (“No”), it isdiscarded (“Discard Packet”) 428. If it is new (“Yes”), then it isassessed for emergency prioritization (“Is Packet Emergency Priority?”)429. If the packet is emergency-priority (“Yes”), it is queued (“QueueEmergency Information”) 430 for review by the OSC. If it is not valid(“No”), then it is evaluated for positional data (“Does Packet ContainPositional Data?”) 431. If it contains positional data (“Yes”), the LPEupdates the device's position in the base station's memory and queues itfor transmission across the network, ultimately to the device (“UpdateUnit Position in Memory and Queue”) 432. If no positional data iscontained in the packet (“No”), The packet is then assessed forbiometric data (“Does Packet Contain Biometric Data?”) 433. If biometricdata is present in the packet (“Yes”), the data is stored in the basestation's memory and queued for transmission to the device through thenetwork (“Update Personnel Biometric Information and Queue”) 434.Finally, all queued updates (emergency information, position andbiometrics) are transmitted 435 throughout the UWB network, as well asvia WI-FI link to the incident server.

Concomitantly with the above phases, each anchor, IGLU and EEL isperforming complementary and/or relaying tasks to those of the basestation. In the case of each anchor, the “Off-Cycle” actions (i.e.,registration on the UWB network) are described above. At the start ofthe Cycle Prep phase, each anchor retrieves its storedpositional-movement data (“Retrieve Stored Velocity/Bearing Delta”) 436to determine whether the anchor has moved out of tolerance to bereliable (“Has Unit Physically Moved Beyond Tolerance?”) 437. If it has(“Yes”) it will prepare a recalibration packet (“Prepare RecalibrationPacket”) 438 to be sent at the start of its comm window (“Start CommsWindow”) 439. If it has not (“No”), then the anchor will gatherinformation about its status (“Gather Device Status”) 440 and determinewhether a change to that status has occurred since the last cycle (“HasStatus Changed?”) 441. If it has changed (“Yes”), it will prepare astatus change packet (“Prepare Packet Status Change”) 442 to be sent tothe base station through the network. It will then prepare any receiveddata packets to be sent queued (“Prepare Received Data Packets”) 443 andsent during its normal comm window, and await the Cycle Sync phase(“Await Cycle Sync”) 444.

During the Cycle Sync 407 phase, each anchor will receive the newtimetable broadcast from the base station over the local UWB network(“New Timetable Received”) 445, synching its local cycle clock (“SyncLocal Cycle Clock”) 446, processing the timetable and immediatelyretransmitting the same (“Process Timetable and Immediately RetransmitTimetable”) 447 and await cycle start 448.

During the Cycle Execution phase 409, at the start of each anchor's commwindow (“Start Comms Window”) 439 the queued packets (i.e., thoseaggregated in the Cycle Prep phase) are “iterated through” (“IterateThrough Queued Packets”) 449—until the comms window ends 456 that is,arranged for transmission in a “first-in, first-out” lineup and sentover multiple comm windows, if sufficient time is unavailable within thecurrent comm window—during the anchor's comm window(s), as follows: Theprocessor in the anchor determines the total number of packets needed tobe transmitted (“Do Additional Packets Exist Beyond the CurrentPacket?”) 450, and if additional packets (“Do Additional Packets ExistBeyond the Current Packet?”) 451 must be transmitted beyond the currentpacket (“Yes”), the anchor's processor determines whether the estimatedtime available for transmitting the additional packets is sufficient(“Is Time Available in Comms Window for Additional Packets?”) 452. If itis (“Yes”), the packet(s) is(are) sent in the current comm window, andthe last data packet is marked as the final one to be transmitted (“MarkPacket as Final Transmission”) 453 and the packets are all transmittedduring the current comm window (“Transmit Queued Packet”) 454. If moretime is needed, the remaining packet(s) is(are) marked as pending andqueued for transmission during the next comm window (“Mark Packet asAdditional Packets Pending”) 455.

During the Cycle Execution 409 but outside the anchor's comm window,standby-window functions are performed (“Start Standby Window”) 457.These are gathering (“Gather Raw Velocity/Bearing Sensor Data”) 458,calculating and storing AGM's movement data (“Calculate and StoreMovement Delta Since Last Transmission”) 459; receiving (“PacketReceived”) 424, processing and queuing other data packets (validitydetermination and storage is as described above) for transmission duringits comm window ending the standby window 461.

Cycle Prep, Cycle Sync, Cycle Execution and Off-Cycle phases for theother devices are the same as for each anchor, with the followingexceptions. During Cycle Prep, each IGLU 140 retrieves its storedAGM-derived movement data (“Retrieve Stored Velocity/Bearing Delta”) 436and prepares it for transmission during its comm window (“PreparePositioning Packet”) 463. Each IGLU also pairs 464 with and retrieves465 information from its paired BMU, as described above, and sends thesame—along with its AGM-derived movement data—during its comm window.The BMU receives the request for information 466 and sends back to theIGLU 140 biometric data 467. The IGLU 140 receives the biometric data468 and prepares a biometric packet 469. The functioning of each EEL isthe same as that for each anchor, except that the EEL does not containan AGM, so no EEL acceleration data is transmitted in its data packet(although such data from other received data packets are of coursetransmitted).

The flowcharts included in this description and in the attached figuresare examples of the methodology which may be used for the localizationand monitoring of personnel in austere environs. In this description, itwill be understood that each block of the flowchart illustrations, andcombinations of blocks in the flowchart illustrations, can beimplemented by computer program instructions. These computer programinstructions may be loaded onto a computer or other programmableapparatus to produce a machine such that the instructions that executeon the computer or other programmable apparatus create means forimplementing the functions specified in the flowchart block or blocks.These computer program instructions may also be stored in acomputer-readable memory that can direct a computer or otherprogrammable apparatus to function in a particular manner such that theinstructions stored in the computer-readable memory produce an articleof manufacture including instruction means that implement the functionspecified in the flowchart block or blocks. The computer programinstructions may also be loaded onto a computer or other programmableapparatus to cause a series of operational steps to be performed in thecomputer or on the other programmable apparatus to produce a computerimplemented process such that the instructions that execute on thecomputer or other programmable apparatus provide steps for implementingthe functions specified in the flowchart block or blocks.

Accordingly, blocks of the flowchart illustrations support combinationsof means for performing the specified functions and combinations ofsteps for performing the specified functions. It will also be understoodthat each block of the flowchart illustrations, and combinations ofblocks in the flowchart illustrations, can be implemented by specialpurpose hardware-based computer systems that perform the specifiedfunctions or steps, or combinations of special purpose hardware andcomputer instructions.

Consistent with the process described above, FIG. 5 presents ahigh-level flowchart user geolocation in an austere environment,according to one embodiment of the present invention. The process begins505 upon arrival at an austere location with the establishment 510 of abase station. Shortly thereafter a plurality of anchors is positioned515 proximate to the austere environment but within communication of thebase station. Ideally and as described herein, each anchor is in aline-of-sight communication with either the base station or anotheranchor. With the base station and anchors positioned, a localgeolocation network is established 520 around the austere environment.

Each user (First Responder (FR)) is associated 525 with an IGLU and eachIGLU is associated 530 with a BMU. Once associated with a user each IGLUregisters with the Base Station and a communication plan is established540 between the Base Station and each IGLU.

As previously described each IGLU provides, and the Base Stationreceived 545, IGLU data from which the Base Station can determine anIGLU location and monitor biometric data of the associated user. Usingthis data, the base station determines and assigns 555 a dwell time foreach IGLU.

As the event unfolds, the on-scene commander monitors the location andstatus of each user in the environment. Using the established dwelltimes and the communication protocols discussed herein, a degree of IGLUlocation confidence is assigned to each IGLU. Responsive 560 to thatdegree of IGLU location confidence dropping below a predefined limit,the base station modifies 565 periodic dwell time placing a priority onraising the location confidence of the IGLU's which have dropped belowthe predefined limit. Upon re-establishing locational confidence, thedwell times are reassigned for normal operations.

Similarly, when the base station identifies 570 a user in distress basedon monitoring the biometric data, periodic dwell time is again modified565 to increase location confidence of that particular user. In somecases, the IGLU locational confidence may have not dropped below thepredefined limit, however the raised concern for the user's wellbeingjustifies a high degree of locational awareness and thus a modifieddwell time. Once biometric data indicates the distress is no longerpresent, normal dwell times are resumed with each IGLU location and theassociated user's biometric data being monitored 575, ending 595 theprocess.

Some portions of this specification are presented in terms of algorithmsor symbolic representations of operations on data stored as bits orbinary digital signals within a machine memory (e.g., a computermemory). These algorithms or symbolic representations are examples oftechniques used by those of ordinary skill in the data processing artsto convey the substance of their work to others skilled in the art. Asused herein, an “algorithm” is a self-consistent sequence of operationsor similar processing leading to a desired result. In this context,algorithms and operations involve the manipulation of informationelements. Typically, but not necessarily, such elements may take theform of electrical, magnetic, or optical signals capable of beingstored, accessed, transferred, combined, compared, or otherwisemanipulated by a machine. It is convenient at times, principally forreasons of common usage, to refer to such signals using words such as“data,” “content,” “bits,” “values,” “elements,” “symbols,”“characters,” “terms,” “numbers,” “numerals,” “words”, or the like.These specific words, however, are merely convenient labels and are tobe associated with appropriate information elements.

The features and advantages described in this disclosure are notall-inclusive. Many additional features and advantages will be apparentto one of ordinary skill in the relevant art in view of the drawings,specification, and claims hereof. Moreover, it should be noted that thelanguage used in the specification has been principally selected forreadability and instructional purposes and may not have been selected todelineate or circumscribe the inventive subject matter; reference to theclaims is necessary to determine such inventive subject matter.

The preceding description with reference to the accompanying drawings isprovided to assist in a comprehensive understanding of exemplaryembodiments of the present invention as defined by the claims and theirequivalents. It includes various specific details to assist in thatunderstanding but these are to be regarded as merely exemplary.Accordingly, those of ordinary skill in the art will recognize thatvarious changes and modifications of the embodiments described hereincan be made without departing from the scope and spirit of theinvention. Also, descriptions of well-known functions and constructionsare omitted for clarity and conciseness.

Unless specifically stated otherwise, discussions herein using wordssuch as “processing,” “computing,” “calculating,” “determining,”“presenting,” “displaying,” or the like may refer to actions orprocesses of a machine (e.g., a computer) that manipulates or transformsdata represented as physical (e.g., electronic, magnetic, or optical)quantities within one or more memories (e.g., volatile memory,non-volatile memory, or a combination thereof), registers, or othermachine components that receive, store, transmit, or displayinformation.

It will also be understood by those familiar with the art, that theinvention may be embodied in other specific forms without departing fromthe spirit or essential characteristics thereof. Likewise, theparticular naming and division of the modules, managers, functions,systems, engines, layers, features, attributes, methodologies, and otheraspects are not mandatory or significant, and the mechanisms thatimplement the invention or its features may have different names,divisions, and/or formats. Furthermore, as will be apparent to one ofordinary skill in the relevant art, the modules, managers, functions,systems, engines, layers, features, attributes, methodologies, and otheraspects of the invention can be implemented as software, hardware,firmware, or any combination of the three.

Of course, wherever a component of the present invention is implementedas software, the component can be implemented as a script, as astandalone program, as part of a larger program, as a plurality ofseparate scripts and/or programs, as a statically or dynamically linkedlibrary, as a kernel loadable module, as a device driver, and/or inevery and any other way known now or in the future to those of skill inthe art of computer programming. Additionally, the present invention isin no way limited to implementation in any specific programminglanguage, or for any specific operating system or environment.Accordingly, the disclosure of the present invention is intended to beillustrative, but not limiting, of the scope of the invention, which isset forth in the following claims.

Software programming code which embodies the present invention istypically accessed by a microprocessor from long-term, persistentstorage media of some type, such as a flash drive or hard drive. Thesoftware programming code may be embodied on any of a variety of knownmedia for use with a data processing system, such as a diskette, harddrive, CD-ROM, or the like. The code may be distributed on such media ormay be distributed from the memory or storage of one computer systemover a network of some type to other computer systems for use by suchother systems. Alternatively, the programming code may be embodied inthe memory of the device and accessed by a microprocessor using aninternal bus. The techniques and methods for embodying softwareprogramming code in memory, on physical media, and/or distributingsoftware code via networks are well known and will not be furtherdiscussed herein.

Generally, program modules include routines, programs, objects,components, data structures and the like that perform particular tasksor implement particular abstract data types. Moreover, those skilled inthe art will appreciate that the invention can be practiced with othercomputer system configurations, including hand-held devices,multi-processor systems, microprocessor-based or programmable consumerelectronics, network PCs, minicomputers, mainframe computers, and thelike. The invention may also be practiced in distributed computingenvironments where tasks are performed by remote processing devices thatare linked through a communications network. In a distributed computingenvironment, program modules may be located in both local and remotememory storage devices.

An exemplary system for implementing the invention includes a generalpurpose computing device such as the form of a conventional personalcomputer, a personal communication device or the like, including aprocessing unit, a system memory, and a system bus that couples varioussystem components, including the system memory to the processing unit.The system bus may be any of several types of bus structures including amemory bus or memory controller, a peripheral bus, and a local bus usingany of a variety of bus architectures. The system memory generallyincludes read-only memory (ROM) and random-access memory (RAM). A basicinput/output system (BIOS), containing the basic routines that help totransfer information between elements within the computer, such asduring start-up, is stored in ROM. The computer may further include ahard disk drive for reading from and writing to a hard disk, a magneticdisk drive for reading from or writing to a removable magnetic disk. Thehard disk drive and magnetic disk drive are connected to the system busby a hard disk drive interface and a magnetic disk drive interface,respectively. The drives and their associated computer-readable mediaprovide non-transitory, non-volatile storage of computer readableinstructions, data structures, program modules and other data for thepersonal computer. Although the exemplary environment described hereinemploys a hard disk and a removable magnetic disk, it should beappreciated by those skilled in the art that other types of computerreadable media which can store data that is accessible by a computer mayalso be used in the exemplary operating environment.

While there have been described above the principles of the presentinvention in conjunction with a system and associated methodology forpersonal location and monitoring in austere environments, it is to beclearly understood that the foregoing description is made only by way ofexample and not as a limitation to the scope of the invention.Particularly, it is recognized that the teachings of the foregoingdisclosure will suggest other modifications to those persons skilled inthe relevant art. Such modifications may involve other features that arealready known per se and which may be used instead of or in addition tofeatures already described herein. Although claims have been formulatedin this application to particular combinations of features, it should beunderstood that the scope of the disclosure herein also includes anynovel feature or any novel combination of features disclosed eitherexplicitly or implicitly or any generalization or modification thereofwhich would be apparent to persons skilled in the relevant art, whetheror not such relates to the same invention as presently claimed in anyclaim and whether or not it mitigates any or all of the same technicalproblems as confronted by the present invention. The Applicant herebyreserves the right to formulate new claims to such features and/orcombinations of such features during the prosecution of the presentapplication or of any further application derived therefrom.

We claim:
 1. A system for geolocation in austere environmentscomprising: one or more anchors wherein each anchor includes a GlobalNavigation Satellite System (GNSS) receiver configured to determine anAnchor Location (AL), and wherein each anchor includes at least oneultrawideband (UWB) transceiver; one or more Individual GeoLocationUnits (IGLUs), wherein at least one IGLU is associated with a user andwherein each IGLU includes at least one UWB transceiver configured toprovide two-way ranging and a plurality of accelerometers configured tomeasure motion of the IGLU, and is further associated with a BiometricMonitoring Unit (BMU) configured to measure User Biometric Data (UBD) ofthe IGLU; and a base station communicatively coupled to each anchorand/or each IGLU in a localized, bounded network, wherein the basestation includes at least one ultrawideband (UWB) transceiver and aLocation Processing Engine (LPE) configured to receive IGLU data fromeach IGLU, and wherein each IGLU is associated with an IGLU location(IL) computed by the LPE from the IGLU data received from that IGLU, anda position confidence in the IL based on received IGLU data, and whereinthe base station, responsive to the position confidence dropping below apredetermined threshold from one of the one or more IGLUs, modifies acommunication window for listening for UWB signals from the one of theone or more IGLUs to re-establish the position confidence above thepredetermined threshold.
 2. The system for geolocation in austereenvironments according to claim 1, wherein each IGLU is configured totransmit, using the at least one UWB transmitter, IGLU data using one ormore data packets.
 3. The system for geolocation in austere environmentsaccording to claim 1, wherein one of the one or more anchors is the basestation and wherein each other anchor relays IGLU data to the basestation.
 4. The system for geolocation in austere environments accordingto claim 1, wherein each IGLU is configured to relay the IL of anotherIGLU to the base station and/or the one or more anchors.
 5. The systemfor geolocation in austere environments according to claim 1, whereinthe base station determines IL using MLAT of received IGLU data and GNSSdata of each anchor.
 6. The system for geolocation in austereenvironments according to claim 5, wherein the LPE is configured,responsive to LPE confidence in IL falling below a predetermined limit,to modify the communication window to increase LPE confidence in IL. 7.The system for geolocation in austere environments according to claim 3,wherein the LPE is configured, responsive to UBD indicating distress, tomodify the communication window to increase LPE confidence in IL.
 8. Amethod for geolocation of a user in austere environments, the methodcomprising: establishing a local geolocation network by one or moreanchors wherein each anchor is associated with an Anchor Location (AL)and each anchor includes at least one ultrawideband (UWB) transceiverand a Global Navigation Satellite System (GNSS) receiver and wherein oneof the anchors is configured as a base station having a LocationProcessing Engine (LPE); associating with the user an IndividualGeoLocation Unit (IGLU) from among one or more IGLUs, wherein each IGLUincludes at least one UWB transceiver configured to provide two-wayranging and a plurality of accelerometers configured to measure motionof the IGLU, and wherein each IGLU associates with a BiometricMonitoring Unit (BMU) configured to measure User Biometric Data (UBD) ofthe user; receiving, at the base station, IGLU data; determining, at thebase station, an IGLU location (IL) based on received IGLU data whereinthe LPE determines a LPE confidence in the IL; and assigning, at thebase station, responsive to the LPE confidence in the IL dropping belowa predetermined threshold from one of the one or more IGLUs, acommunication window for listening for UWB signals from the one of theone or more IGLUs to re-establish the LPE confidence above thepredetermined threshold.
 9. The method for geolocation of a user inaustere environments according to claim 8, further comprisingtransmitting by the IGLU, IGLU data using one or more data packets. 10.The method for geolocation of a user in austere environments accordingto claim 8, further comprising relaying by each anchor to the basestation received IGLU data.
 11. The method for geolocation of a user inaustere environments according to claim 8, wherein determining includesusing MLAT of received IGLU data and GNSS data of each anchor.
 12. Themethod for geolocation of a user in austere environments according toclaim 8, wherein responsive to LPE confidence in IL falling below apredetermined limit, further comprising modifying communication windowassignments to increase LPE confidence in IL.
 13. The method forgeolocation of a user in austere environments according to claim 8,wherein responsive to UBD indicating distress, modifying communicationwindow assignments to increase LPE confidence in IL.
 14. Anon-transitory machine-readable storage medium having stored thereoninstructions for personnel geolocation in an austere environment,comprising machine executable code, which when executed by at least onemachine, causes the machine to: associate with the user an IndividualGeoLocation Unit (IGLU) wherein each IGLU includes at least one UWBtransceiver configured to provide two-way ranging and a plurality ofaccelerometers configured to measure motion of the IGLU, and toassociate with each IGLU a Biometric Monitoring Unit (BMU) configured tomeasure User Biometric Data (UBD) of the user; receive, at the basestation, IGLU data; determine, at the base station, an IGLU location(IL) based on received IGLU data wherein the LPE determines a LPEconfidence in the IL; and assign, at the base station, responsive to theLPE confidence in the IL dropping below a predetermined threshold fromone of the one or more IGLUs, a communication window for listening forUWB signals from the one of the one or more IGLUs to re-establish theposition confidence above the predetermined threshold.
 15. Thenon-transitory machine-readable storage medium for claim 14, furthercomprising machine executable code which causes the machine to transmitby the IGLU, IGLU data using one or more data packets.
 16. Thenon-transitory machine-readable storage medium for claim 14, furthercomprising machine executable code which causes the machine to relay byeach anchor to the base station received IGLU data.
 17. Thenon-transitory machine-readable storage medium for claim 14, furthercomprising machine executable code which causes the machine to determineincludes using MLAT of received IGLU data and GNSS data of each anchor.18. The non-transitory machine-readable storage medium for claim 14,further comprising machine executable code which, responsive to LPEconfidence in IL falling below a predetermined limit, causes the machineto modify communication window assignments to increase LPE confidence inIL.
 19. The non-transitory machine-readable storage medium for claim 14,further comprising machine executable code which, responsive to UBDindicating distress, causes the machine to modify communication windowassignments to increase LPE confidence in IL.